diff options
Diffstat (limited to 'drivers/macintosh/via-cuda.c')
| -rw-r--r-- | drivers/macintosh/via-cuda.c | 294 |
1 files changed, 210 insertions, 84 deletions
diff --git a/drivers/macintosh/via-cuda.c b/drivers/macintosh/via-cuda.c index 2088e23a8002..c60415958dfe 100644 --- a/drivers/macintosh/via-cuda.c +++ b/drivers/macintosh/via-cuda.c @@ -1,10 +1,10 @@ /* - * Device driver for the via-cuda on Apple Powermacs. + * Device driver for the Cuda and Egret system controllers found on PowerMacs + * and 68k Macs. * - * The VIA (versatile interface adapter) interfaces to the CUDA, - * a 6805 microprocessor core which controls the ADB (Apple Desktop - * Bus) which connects to the keyboard and mouse. The CUDA also - * controls system power and the RTC (real time clock) chip. + * The Cuda or Egret is a 6805 microcontroller interfaced to the 6522 VIA. + * This MCU controls system power, Parameter RAM, Real Time Clock and the + * Apple Desktop Bus (ADB) that connects to the keyboard and mouse. * * Copyright (C) 1996 Paul Mackerras. */ @@ -50,10 +50,27 @@ static DEFINE_SPINLOCK(cuda_lock); #define IER (14*RS) /* Interrupt enable register */ #define ANH (15*RS) /* A-side data, no handshake */ -/* Bits in B data register: all active low */ -#define TREQ 0x08 /* Transfer request (input) */ -#define TACK 0x10 /* Transfer acknowledge (output) */ -#define TIP 0x20 /* Transfer in progress (output) */ +/* + * When the Cuda design replaced the Egret, some signal names and + * logic sense changed. They all serve the same purposes, however. + * + * VIA pin | Egret pin + * ----------------+------------------------------------------ + * PB3 (input) | Transceiver session (active low) + * PB4 (output) | VIA full (active high) + * PB5 (output) | System session (active high) + * + * VIA pin | Cuda pin + * ----------------+------------------------------------------ + * PB3 (input) | Transfer request (active low) + * PB4 (output) | Byte acknowledge (active low) + * PB5 (output) | Transfer in progress (active low) + */ + +/* Bits in Port B data register */ +#define TREQ 0x08 /* Transfer request */ +#define TACK 0x10 /* Transfer acknowledge */ +#define TIP 0x20 /* Transfer in progress */ /* Bits in ACR */ #define SR_CTRL 0x1c /* Shift register control bits */ @@ -65,6 +82,74 @@ static DEFINE_SPINLOCK(cuda_lock); #define IER_CLR 0 /* clear bits in IER */ #define SR_INT 0x04 /* Shift register full/empty */ +/* Duration of byte acknowledgement pulse (us) */ +#define EGRET_TACK_ASSERTED_DELAY 300 +#define EGRET_TACK_NEGATED_DELAY 400 + +/* Interval from interrupt to start of session (us) */ +#define EGRET_SESSION_DELAY 450 + +#ifdef CONFIG_PPC +#define mcu_is_egret false +#else +static bool mcu_is_egret; +#endif + +static inline bool TREQ_asserted(u8 portb) +{ + return !(portb & TREQ); +} + +static inline void assert_TIP(void) +{ + if (mcu_is_egret) { + udelay(EGRET_SESSION_DELAY); + out_8(&via[B], in_8(&via[B]) | TIP); + } else + out_8(&via[B], in_8(&via[B]) & ~TIP); +} + +static inline void assert_TIP_and_TACK(void) +{ + if (mcu_is_egret) { + udelay(EGRET_SESSION_DELAY); + out_8(&via[B], in_8(&via[B]) | TIP | TACK); + } else + out_8(&via[B], in_8(&via[B]) & ~(TIP | TACK)); +} + +static inline void assert_TACK(void) +{ + if (mcu_is_egret) { + udelay(EGRET_TACK_NEGATED_DELAY); + out_8(&via[B], in_8(&via[B]) | TACK); + } else + out_8(&via[B], in_8(&via[B]) & ~TACK); +} + +static inline void toggle_TACK(void) +{ + out_8(&via[B], in_8(&via[B]) ^ TACK); +} + +static inline void negate_TACK(void) +{ + if (mcu_is_egret) { + udelay(EGRET_TACK_ASSERTED_DELAY); + out_8(&via[B], in_8(&via[B]) & ~TACK); + } else + out_8(&via[B], in_8(&via[B]) | TACK); +} + +static inline void negate_TIP_and_TACK(void) +{ + if (mcu_is_egret) { + udelay(EGRET_TACK_ASSERTED_DELAY); + out_8(&via[B], in_8(&via[B]) & ~(TIP | TACK)); + } else + out_8(&via[B], in_8(&via[B]) | TIP | TACK); +} + static enum cuda_state { idle, sent_first_byte, @@ -120,11 +205,13 @@ int __init find_via_cuda(void) struct adb_request req; int err; - if (macintosh_config->adb_type != MAC_ADB_CUDA) + if (macintosh_config->adb_type != MAC_ADB_CUDA && + macintosh_config->adb_type != MAC_ADB_EGRET) return 0; via = via1; cuda_state = idle; + mcu_is_egret = macintosh_config->adb_type == MAC_ADB_EGRET; err = cuda_init_via(); if (err) { @@ -221,7 +308,7 @@ static int __init via_cuda_start(void) return -EAGAIN; } - printk("Macintosh CUDA driver v0.5 for Unified ADB.\n"); + pr_info("Macintosh Cuda and Egret driver.\n"); cuda_fully_inited = 1; return 0; @@ -237,7 +324,8 @@ cuda_probe(void) if (sys_ctrler != SYS_CTRLER_CUDA) return -ENODEV; #else - if (macintosh_config->adb_type != MAC_ADB_CUDA) + if (macintosh_config->adb_type != MAC_ADB_CUDA && + macintosh_config->adb_type != MAC_ADB_EGRET) return -ENODEV; #endif if (via == NULL) @@ -246,12 +334,39 @@ cuda_probe(void) } #endif /* CONFIG_ADB */ +static int __init sync_egret(void) +{ + if (TREQ_asserted(in_8(&via[B]))) { + /* Complete the inbound transfer */ + assert_TIP_and_TACK(); + while (1) { + negate_TACK(); + mdelay(1); + (void)in_8(&via[SR]); + assert_TACK(); + if (!TREQ_asserted(in_8(&via[B]))) + break; + } + negate_TIP_and_TACK(); + } else if (in_8(&via[B]) & TIP) { + /* Terminate the outbound transfer */ + negate_TACK(); + assert_TACK(); + mdelay(1); + negate_TIP_and_TACK(); + } + /* Clear shift register interrupt */ + if (in_8(&via[IFR]) & SR_INT) + (void)in_8(&via[SR]); + return 0; +} + #define WAIT_FOR(cond, what) \ do { \ int x; \ for (x = 1000; !(cond); --x) { \ if (x == 0) { \ - printk("Timeout waiting for " what "\n"); \ + pr_err("Timeout waiting for " what "\n"); \ return -ENXIO; \ } \ udelay(100); \ @@ -261,10 +376,6 @@ cuda_probe(void) static int __init cuda_init_via(void) { - out_8(&via[DIRB], (in_8(&via[DIRB]) | TACK | TIP) & ~TREQ); /* TACK & TIP out */ - out_8(&via[B], in_8(&via[B]) | TACK | TIP); /* negate them */ - out_8(&via[ACR] ,(in_8(&via[ACR]) & ~SR_CTRL) | SR_EXT); /* SR data in */ - (void)in_8(&via[SR]); /* clear any left-over data */ #ifdef CONFIG_PPC out_8(&via[IER], 0x7f); /* disable interrupts from VIA */ (void)in_8(&via[IER]); @@ -272,16 +383,25 @@ __init cuda_init_via(void) out_8(&via[IER], SR_INT); /* disable SR interrupt from VIA */ #endif + out_8(&via[DIRB], (in_8(&via[DIRB]) | TACK | TIP) & ~TREQ); /* TACK & TIP out */ + out_8(&via[ACR], (in_8(&via[ACR]) & ~SR_CTRL) | SR_EXT); /* SR data in */ + (void)in_8(&via[SR]); /* clear any left-over data */ + + if (mcu_is_egret) + return sync_egret(); + + negate_TIP_and_TACK(); + /* delay 4ms and then clear any pending interrupt */ mdelay(4); (void)in_8(&via[SR]); out_8(&via[IFR], SR_INT); /* sync with the CUDA - assert TACK without TIP */ - out_8(&via[B], in_8(&via[B]) & ~TACK); + assert_TACK(); /* wait for the CUDA to assert TREQ in response */ - WAIT_FOR((in_8(&via[B]) & TREQ) == 0, "CUDA response to sync"); + WAIT_FOR(TREQ_asserted(in_8(&via[B])), "CUDA response to sync"); /* wait for the interrupt and then clear it */ WAIT_FOR(in_8(&via[IFR]) & SR_INT, "CUDA response to sync (2)"); @@ -289,14 +409,13 @@ __init cuda_init_via(void) out_8(&via[IFR], SR_INT); /* finish the sync by negating TACK */ - out_8(&via[B], in_8(&via[B]) | TACK); + negate_TACK(); /* wait for the CUDA to negate TREQ and the corresponding interrupt */ - WAIT_FOR(in_8(&via[B]) & TREQ, "CUDA response to sync (3)"); + WAIT_FOR(!TREQ_asserted(in_8(&via[B])), "CUDA response to sync (3)"); WAIT_FOR(in_8(&via[IFR]) & SR_INT, "CUDA response to sync (4)"); (void)in_8(&via[SR]); out_8(&via[IFR], SR_INT); - out_8(&via[B], in_8(&via[B]) | TIP); /* should be unnecessary */ return 0; } @@ -357,6 +476,7 @@ cuda_reset_adb_bus(void) return 0; } #endif /* CONFIG_ADB */ + /* Construct and send a cuda request */ int cuda_request(struct adb_request *req, void (*done)(struct adb_request *), @@ -413,47 +533,43 @@ cuda_write(struct adb_request *req) static void cuda_start(void) { - struct adb_request *req; - /* assert cuda_state == idle */ - /* get the packet to send */ - req = current_req; - if (req == 0) + if (current_req == NULL) return; - if ((in_8(&via[B]) & TREQ) == 0) + data_index = 0; + if (TREQ_asserted(in_8(&via[B]))) return; /* a byte is coming in from the CUDA */ /* set the shift register to shift out and send a byte */ out_8(&via[ACR], in_8(&via[ACR]) | SR_OUT); - out_8(&via[SR], req->data[0]); - out_8(&via[B], in_8(&via[B]) & ~TIP); + out_8(&via[SR], current_req->data[data_index++]); + if (mcu_is_egret) + assert_TIP_and_TACK(); + else + assert_TIP(); cuda_state = sent_first_byte; } void cuda_poll(void) { - /* cuda_interrupt only takes a normal lock, we disable - * interrupts here to avoid re-entering and thus deadlocking. - */ - if (cuda_irq) - disable_irq(cuda_irq); - cuda_interrupt(0, NULL); - if (cuda_irq) - enable_irq(cuda_irq); + cuda_interrupt(0, NULL); } EXPORT_SYMBOL(cuda_poll); +#define ARRAY_FULL(a, p) ((p) - (a) == ARRAY_SIZE(a)) + static irqreturn_t cuda_interrupt(int irq, void *arg) { - int status; + unsigned long flags; + u8 status; struct adb_request *req = NULL; unsigned char ibuf[16]; int ibuf_len = 0; int complete = 0; - spin_lock(&cuda_lock); + spin_lock_irqsave(&cuda_lock, flags); /* On powermacs, this handler is registered for the VIA IRQ. But they use * just the shift register IRQ -- other VIA interrupt sources are disabled. @@ -466,52 +582,50 @@ cuda_interrupt(int irq, void *arg) #endif { if ((in_8(&via[IFR]) & SR_INT) == 0) { - spin_unlock(&cuda_lock); + spin_unlock_irqrestore(&cuda_lock, flags); return IRQ_NONE; } else { out_8(&via[IFR], SR_INT); } } - - status = (~in_8(&via[B]) & (TIP|TREQ)) | (in_8(&via[ACR]) & SR_OUT); - /* printk("cuda_interrupt: state=%d status=%x\n", cuda_state, status); */ + + status = in_8(&via[B]) & (TIP | TACK | TREQ); + switch (cuda_state) { case idle: - /* CUDA has sent us the first byte of data - unsolicited */ - if (status != TREQ) - printk("cuda: state=idle, status=%x\n", status); + /* System controller has unsolicited data for us */ (void)in_8(&via[SR]); - out_8(&via[B], in_8(&via[B]) & ~TIP); +idle_state: + assert_TIP(); cuda_state = reading; reply_ptr = cuda_rbuf; reading_reply = 0; break; case awaiting_reply: - /* CUDA has sent us the first byte of data of a reply */ - if (status != TREQ) - printk("cuda: state=awaiting_reply, status=%x\n", status); + /* System controller has reply data for us */ (void)in_8(&via[SR]); - out_8(&via[B], in_8(&via[B]) & ~TIP); + assert_TIP(); cuda_state = reading; reply_ptr = current_req->reply; reading_reply = 1; break; case sent_first_byte: - if (status == TREQ + TIP + SR_OUT) { + if (TREQ_asserted(status)) { /* collision */ out_8(&via[ACR], in_8(&via[ACR]) & ~SR_OUT); (void)in_8(&via[SR]); - out_8(&via[B], in_8(&via[B]) | TIP | TACK); + negate_TIP_and_TACK(); cuda_state = idle; + /* Egret does not raise an "aborted" interrupt */ + if (mcu_is_egret) + goto idle_state; } else { - /* assert status == TIP + SR_OUT */ - if (status != TIP + SR_OUT) - printk("cuda: state=sent_first_byte status=%x\n", status); - out_8(&via[SR], current_req->data[1]); - out_8(&via[B], in_8(&via[B]) ^ TACK); - data_index = 2; + out_8(&via[SR], current_req->data[data_index++]); + toggle_TACK(); + if (mcu_is_egret) + assert_TACK(); cuda_state = sending; } break; @@ -521,7 +635,7 @@ cuda_interrupt(int irq, void *arg) if (data_index >= req->nbytes) { out_8(&via[ACR], in_8(&via[ACR]) & ~SR_OUT); (void)in_8(&via[SR]); - out_8(&via[B], in_8(&via[B]) | TACK | TIP); + negate_TIP_and_TACK(); req->sent = 1; if (req->reply_expected) { cuda_state = awaiting_reply; @@ -534,26 +648,37 @@ cuda_interrupt(int irq, void *arg) } } else { out_8(&via[SR], req->data[data_index++]); - out_8(&via[B], in_8(&via[B]) ^ TACK); + toggle_TACK(); + if (mcu_is_egret) + assert_TACK(); } break; case reading: - *reply_ptr++ = in_8(&via[SR]); - if (status == TIP) { + if (reading_reply ? ARRAY_FULL(current_req->reply, reply_ptr) + : ARRAY_FULL(cuda_rbuf, reply_ptr)) + (void)in_8(&via[SR]); + else + *reply_ptr++ = in_8(&via[SR]); + if (!TREQ_asserted(status)) { + if (mcu_is_egret) + assert_TACK(); /* that's all folks */ - out_8(&via[B], in_8(&via[B]) | TACK | TIP); + negate_TIP_and_TACK(); cuda_state = read_done; + /* Egret does not raise a "read done" interrupt */ + if (mcu_is_egret) + goto read_done_state; } else { - /* assert status == TIP | TREQ */ - if (status != TIP + TREQ) - printk("cuda: state=reading status=%x\n", status); - out_8(&via[B], in_8(&via[B]) ^ TACK); + toggle_TACK(); + if (mcu_is_egret) + negate_TACK(); } break; case read_done: (void)in_8(&via[SR]); +read_done_state: if (reading_reply) { req = current_req; req->reply_len = reply_ptr - req->reply; @@ -570,6 +695,7 @@ cuda_interrupt(int irq, void *arg) } current_req = req->next; complete = 1; + reading_reply = 0; } else { /* This is tricky. We must break the spinlock to call * cuda_input. However, doing so means we might get @@ -581,21 +707,19 @@ cuda_interrupt(int irq, void *arg) ibuf_len = reply_ptr - cuda_rbuf; memcpy(ibuf, cuda_rbuf, ibuf_len); } - if (status == TREQ) { - out_8(&via[B], in_8(&via[B]) & ~TIP); + reply_ptr = cuda_rbuf; + cuda_state = idle; + cuda_start(); + if (cuda_state == idle && TREQ_asserted(in_8(&via[B]))) { + assert_TIP(); cuda_state = reading; - reply_ptr = cuda_rbuf; - reading_reply = 0; - } else { - cuda_state = idle; - cuda_start(); } break; default: - printk("cuda_interrupt: unknown cuda_state %d?\n", cuda_state); + pr_err("cuda_interrupt: unknown cuda_state %d?\n", cuda_state); } - spin_unlock(&cuda_lock); + spin_unlock_irqrestore(&cuda_lock, flags); if (complete && req) { void (*done)(struct adb_request *) = req->done; mb(); @@ -614,8 +738,6 @@ cuda_interrupt(int irq, void *arg) static void cuda_input(unsigned char *buf, int nb) { - int i; - switch (buf[0]) { case ADB_PACKET: #ifdef CONFIG_XMON @@ -632,10 +754,14 @@ cuda_input(unsigned char *buf, int nb) #endif /* CONFIG_ADB */ break; + case TIMER_PACKET: + /* Egret sends these periodically. Might be useful as a 'heartbeat' + * to trigger a recovery for the VIA shift register errata. + */ + break; + default: - printk("data from cuda (%d bytes):", nb); - for (i = 0; i < nb; ++i) - printk(" %.2x", buf[i]); - printk("\n"); + print_hex_dump(KERN_INFO, "cuda_input: ", DUMP_PREFIX_NONE, 32, 1, + buf, nb, false); } } |